Police in Northern Ireland have confirmed that they have charged three men in connection with the discovery of a new type of terrorist mortar weapon in Derry.

A Police Service of Northern Ireland (PSNI) spokesman said on Saturday night that detectives from its Serious Crime Branch investigating ongoing dissident republican activity in the city have charged two 47-year-old men as well as a 40-year-old man.

The charges include possession of explosives with intent to endanger life, conspiracy to murder, and possession of articles for use in terrorism. The trio are due to appear in Derry magistrates court this Monday. A 41-year-old man also arrested in Derry during a security operation last week has been released unconditionally.

The arrests came after the PSNI operation in the Creggan area in which police found a horizontal mortar device similar to those used against British and US troops in Iraq and Afghanistan.

The capture of the weapon, and the detentions, are a major blow to the new IRA terror alliance that has been active in Derry over the past few years.